Refrigeration is mandatory after reconstitution
The product sold by clinics is a synthetic 15-amino-acid peptide manufactured by "solid-phase synthesis", administered under the skin, into the muscle or a joint, or intravenously, often at higher doses for weeks
Based on these clinical trials, researchers concluded that semaglutide injections are effective for treating obesity or people who are overweight
Fasted administration is critical because the peptide works by stimulating lipolysis (fat breakdown) through beta-3 adrenergic receptor activation
In diet-induced obese mice, 30 days of once-daily subcutaneous dosing limited fat-mass gain to 1.3 g versus 4.7 g in controls, but only at 32 mg/kg/day
Evidence snapshot: The strongest human evidence comes from a 2-year randomized controlled trial in 65 healthy older adults (Nass et al., 2008, Annals of Internal Medicine) showing sustained GH/IGF-1 increases and preserved fat-free mass, plus an earlier short-term human polysomnography study on sleep (Copinschi et al., 1997, Neuroendocrinology, PMID 9349662)